Aquarium



FIG. 1 is a front elevation view of an aquarium showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a right side elevation view thereof, the left side view being a mirror image;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a rear elevation view thereof; and,

FIG. 6 is a perspective view thereof. 

The ornamental design for an aquarium, as shown. 